Wood densification and thermal modification: hardness, set-recovery and micromorphology Show others and affiliations
2016 (English) In: Wood Science and Technology, ISSN 0043-7719, E-ISSN 1432-5225, Vol. 50, no 5, p. 883-894Article in journal (Refereed) Published
Abstract [en]
The density of wood can be increased by compressing the porous structure under suitable moisture and temperature conditions. One aim of such densification is to improve surface hardness, and therefore, densified wood might be particularly suitable for flooring products. After compression, however, the deformed wood material is sensitive to moisture, and in this case, recovered up to 60 % of the deformation in water-soaking. This phenomenon, termed set-recovery, was reduced by thermally modifying the wood after densification. This study presents the influence of compression ratio (CR = 40, 50, 60 %) and thermal modification time (TM = 2, 4, 6 h) on the hardness and set-recovery of densified wood. Previously, set-recovery has mainly been studied separately from other properties of densified wood, while in this work, set-recovery was also studied in relation to hardness. The results show that set-recovery was almost eliminated with TM 6 h in the case of CR 40 and 50 %. Hardness significantly increased due to densification and even doubled compared to non-densified samples with a CR of 50 %. Set-recovery reduced the hardness of densified (non-TM) wood back to the original level. TM maintained the hardness of densified wood at an increased level after set-recovery. However, some reduction in hardness was recorded even if set-recovery was almost eliminated.
Place, publisher, year, edition, pages Springer Berlin/Heidelberg, 2016. Vol. 50, no 5, p. 883-894
Keywords [en]
Compression Ratio, Densified Wood, Wood Compression, Thermal Modification, Brinell Hardness
National Category
Natural Sciences
Identifiers URN: urn:nbn:se:ri:diva-404 DOI: 10.1007/s00226-016-0835-z Scopus ID: 2-s2.0-84969895593 OAI: oai:DiVA.org:ri-404 DiVA, id: diva2:941581
2016-06-222016-06-222020-12-01 Bibliographically approved